Attachable impedance



July 13, 1943.

H. K. ANDREWS ATTACHABLE IMPEDANCE Filed April 15, 1941 vllllllillll Patented July 13, 1943 ATTACHABLE IIVIPEDANCE Harold K. Andrews, Stratford, Conn, assignor to Edwin G. Gaynor, Fairfield, Conn.

Application April 15, 19 11, Serial No. 388,633

9 Claims.

This invention relates to new and useful improvements in electrical devices and has particular relation to an attachable impedance such as may be used with a fluorescent lamp or the like.

The objects and advantages of the invention will become apparent from a consideration of the following detailed description taken in connection with the accompanying drawing wherein a satisfactory embodiment of the invention is shown. However, it is to be understood that the invention is not limited to the details disclosed but includes all such variations and modifications as fall within the spiirt of the invention and the scope of the appended claims.

In the drawing:

Fig. 1 is a side elevational view of the attachable impedance of the invention a portion of the casing being broken away;

Fig. 2 is a bottom plan view of the device of the invention;

Fig. 3 is an end elevational view thereof on a reduced scale;

Fig. 4 is an elevational view on a reduced scale showing two of the devices of the invention plugged into and secured to a standard double service outlet fixture;

Fig. 5 is a detail sectional view taken as along the line 55 of Fig. 4;

Fig. 6 is a bottom plan view of the casing and impedance of the invention the bottom wall of the casing and parts carried by such wall being omitted;

Fig. 7 is a top plan view of such bottom wall and parts, the same being shown removed from the casing;

Fig. 8 is a view similar to Fig. 7 but with a sheet of insulatin material removed;

Fig. 9 is a sectional view taken as along the line 9-4! of Fig. 7; and

Fig. 10 is a similar view taken as along the line l0!fl of Fig. 7.

Referring in detail to the drawing the attachable impedance device of the invention as herein disclosed includes a metal casing generally designated l0 and comprising a top wall H, end and side walls l3 and 12, respectively, and a removable bottom wall l4. Wall M is provided with a pair of short upstanding flanges l5 each of which carries a laterally projecting lug l6. These lugs enter openings I! in the side walls of the casing for the purpose of securing the bottom wall to the casing.

An impedance device including a coil l8 and laminations I9 is disposed within casing l0 and the laminations have a rather snug fit between the side and end walls of the casing. As best shown in Fig. 6 the coil I8 is provided with exposed contacts 20 and 2|, which may be in the form of spots of solder, facing toward the lower or bottom end of the casing. One end wall [3 of the casing is provided with a notch or opening 22 to permit of the passage of a lead cord 23 containing wires 24.

Disposed on the inner side of the removable wall I4 is a sheet 25 of insulating material and this sheet has a pair of spaced perforations through which are passed contact prongs 2B and 2'! adapted to be inserted in a standard electrical service outlet fixture. A rather large opening 28 in the wall l4 provides for the projection of the prongs 26 and 2'! from the casing without such prongs coming into contact with any part of such casing.

As shown prongs 26 and 2'! are bifurcated being formed from a piece of metal folded upon itself midway its ends. Each prong at its upper end and at the upper side of the sheet 25 is provided with lateral portions whereby the prongs may not be casually pulled out of position through the opening 28.

Disposed on the upper side of sheet 25 are a pair of terminal elements 29 and 30 each including an upwardly bowed terminal portion 3| adapted to have one of the wires 24 soldered or otherwise secured thereto. Element 29 has an upwardly extending tongue-like spring contact portion 32 while the element 30 includes a downturned portion 33 inserted into the upper end portion of the bifurcated prong 28 and clampingly received therein.

A second sheet 34 of insulating material is disposed over the sheet 25 and has perforations through which the terminals 3| and the contact 32 project. Through another opening or perforation in sheet 34 a spring tongue-like contact 35 is inserted into the upper end portion of the bifurcated prong 21 and is clampingly received therein between the sides thereof. Lugs 36 on the edges of the wall M are clinched over onto the sheet 34 and serve to clamp it and the sheet 25 to the wall. This secures the prongs 26 and 2! and the terminals or terminal elements 29 and 3B in. place between the sheets.

After the various parts have been assembled onto the wall E4 and the impedance device has been dropped into the casing It! the wall I4 is assembled with the casing, the lugs l8 being located in the openings I! in the side walls of the casing. Thus the parts are secured together. It is noted that the contacts 32 and 35 are so located with respect to one another that when the wall H3 i mounted on the casing as described the said contacts are brought into yielding engagement with the contacts 2! and 20 on the lower side of impedance coil I8. Therefore when the prongs 26 and 21 are energized a circuit is completed to the terminals 3| through the impedance.

Attention is directed to the fact (see Figs. 2 and 3) that the prongs 26 and 21 are arranged out of the longitudinal center line of the device and toward one side thereof. The purpose of this arrangement will be understood from Figs. 4 and wherein 31 indicates a wall plate of a standard double service outlet fixture. This plate is held in place by the usual screw 38.

With the prongs 26 and 21 of my improved impedance device arranged toward one side, one of the devices may have its prongs inserted into the entrances of one side of the double outlet fixture and the body of the device will be mainly toward one side of the doublev outlet and will not interfere with the full free use of the other side of such outlet. In fact two of the improved de vices of the invention may be plugged into any standard double outlet fixture as in Fig. 4.

For the purpose of preventing casual disconnection of the device of the invention once it has been plugged into a service outlet a clip 3-9 is provided. In Figs. 4 and 5 where twoof the devices of the invention are shown plugged into the respective sides of a double outlet, two clips 39 are used. Each clip includes a hook-like portion 40 hooked through one of the openings I! in a side wall of a casing in over the lug- I6 in said opening. In addition each clip includes a perforated. body portion 4 I In applyin the clips 39 the wall. plate securing screw 38 is removed and the bodies of the clips (the hook-like portions having been inserted in the openings ll of the casings and the prongs of the devices being plugged into the double outlet) are so disposed that their perforations are in alignment with one'another and the screw hole in the wall plate. Then the screw is reinserted and driven home. Thus the screw 38 serves its usual function and also serves toattach the impedance devices of the invention to the wall in such manner that the devices may not be casually disconnected from the outlet into which they have been plugged.

Having thus set forth the nature of my invention, what I claim is:

1. In an attachable impedance device, a casing, an impedance in said casing, terminals in said casing for attachment of a lead cord, contact prongs projecting through a wall of said casing for insertion in a service outlet, electrical connections between said prongs, impedance, and terminals whereby current is supplied to the latter from the prongs through the impedance when the prongs are energized, said casing having an opening in a wall at right angles to the wall through which said prongs project, a clip having a portion inserted in said opening and a portion lying closely along the wall having the opening, and a portion extending outwardly substantially at right angles to the last mentioned wall and substantially in the plane of the prong containing wall, the outwardly extending portion having a perforation so spaced from the prongs the device in place when the prongs are inserted in the outlet.

2. In an attachable impedance, a casing having an open side, a removable Wall for closing said side, an impedance in said casing and including a coil having a pair of contacts facing said open side, said removable wall comprising a metal plate, a first sheet of insulating material on said plate, said plate having an opening therethrough, a pair of prongs passing through said sheet and the opening in the plate and having lateral portions against the inner side of the sheet, a second sheet of insulating material disposed over the first sheet and covering said lateral portions of the prongs, a pair of terminals on the first sheet and including portions exposed through the second sheet for attachment of lead wires, a connection located between the sheets from one terminal to one of said prongs, a spring contact passing through the second sheet and electrically connected with the other prong, a spring contact connected with the other terminal and passing through the second sheet whereby two spring contacts are exposed at the inner side of the second sheet, and said spring contacts located to engage and bear against the contacts of said coil on assembly of said wall on the casing.

3. In an attachable impedance, a casing havin an open side, a removable wall for closing said side, an impedance in said casing and including a coil having a pair of contacts facing said open side of the casing, said removable wall comprising a metal plate, a first sheet of insulating material on said plate, said plate having an opening therethrough, a pair of prongs passing through said sheet and the opening in the plate, a second sheet of insulating material disposed over the first sheet, each of said prongs comprising a bifurcated structure open at its upper end, a pair of terminals on the first sheet and including portions exposed through the second sheet for attachment of lead wires, a connection located between the sheets from one terminal to one of said prongs and including a portion of said terminal inserted into and clamped by said prong, a spring contact passing through the second sheet and electrically connected with the other prong by being inserted therein and clamped thereby, a spring contact connected with the other terminal and passing through the second sheet whereby two spring contacts are exposed at the inner side of the second sheet, and said spring contacts located to engage and bear against the contacts of the coil on assembly of the removable wall with the casing.

4. An attachable impedance device adapted to have an end of a fluorescent lamp cord attached thereto, said device including a casing containing an impedance, prongs projecting from the casing for insertion in aservice outlet, terminals for attachment of a lead cord, connections whereby said terminals are in circuit with the prongs through the impedance, said casing having a bottom wall from which said prongs project, said prongs located eccentrically of the center line of said bottom wall and toward a side wall of the casing whereby a pair of said devices may at the same time be plugged into the respective sides of a standard double service outlet fixture, said casing having an opening in its side wall toward which said prongs are located, a clip having a portion inserted in said opening and a portion lying closely along the wall having the opening, and a portion extending outwardly substantially at right angles to the last mentioned wall and substantially in the plane of the prong containing wall, the outwardly extending portion havin a perforation so spaced from the prongs as to be coaxial with the center face plate securing screw of a dual service outlet when the prongs are received in one side of said outlet, whereby a single securing screw may be inserted through both the clip and the face plate to secure the device in place when the prongs are inserted in the outlet.

5. In an attachable impedance, a casing having an open side, a removable wall for closing said side, an impedance in said casing and including a coil having a fixed pair of contacts, said removable wall comprising a laminated structure including an outer metal sheet, a first insulating sheet on said metal sheet and a second insulating sheet against th first insulating sheet, lugs on the edges of said metal sheet and bent over and clinched against the second insulating sheet whereby the three sheets are secured together into a unit, a pair of prongs passing through the first insulating sheet and the metal sheet and having lateral portions clamped between the insulating sheets, a pair of terminals clamped between the insulating sheets and including portions exposed for attachment of lead wires, a connection from one terminal to one prong and clamped between the insulating sheets, a spring contact electrically connected with the other prong and exposed at the inner side of the second sheet, a spring contact clamped between the insulating sheets and connected with the other terminal and exposed at the inner side of the second insulating sheet whereby both spring contacts are exposed at the inner side of the second insulating sheet, and said spring contacts located to engage and bear against the contacts of said coil on assembly of said wall on the casing.

6. In an attachable impedance, a metal casing having an open side, a removable wall closing said side comprising a metal plate having an opening therethrough, an impedance in said casing and including a coil having a pair of exposed contacts, a pair of prongs passing through the opening in said plate, a pair of terminals, a connection from one of said terminals to one of said prongs, a spring contact electrically connected with the other prong, a spring contact electrically connected with the other terminal, means insulating all of said prongs, terminals and contacts from said plate, means securing said insulating means, plate, prongs, terminals and contacts into a unitary structure, said casing havin openings in a pair of walls, lugs on said plate and entering said openings and securing the plate in position closing said open side of the casing, and said spring contacts located to engage and bear against the contacts of said coil when said wall is secured on the casing.

7. In an attachable impedance, a metal casing having an open side, a removable wall for closing said side comprising a metal plate having an opening therethrough, an impedance in said casing and including a coil having a pair of exposed contacts, a pair of prongs passing through the opening in said plate, a pair of terminals, a connection from one of said terminals to one of said prongs, a spring contact electrically connected with the other prong, a spring contact electrically connected with the other terminal, means insulating all of said prongs, terminals and contacts from said plate, means securing said insulating means, plate, prongs, terminals and contacts into a unitary structure, said spring contacts located to engage and bear against the contacts of said coil when said wall is secured on said casing, and means securing said wall in position closing the open side of said casing.

8. In an attachable impedance device, a casing, an impedance in said casing, terminals in said casing for attachment of leads, contact prongs projecting through a wall of said casing for insertion in a service outlet, electrical connections between said prongs, impedance and terminals whereby current is supplied to the latter from the prongs through the impedance when the prongs are energized, said casing having an opening in a wall at right angles to the wall through which said prongs project, a clip having a portion inserted in said opening and a portion extending outwardly substantially at right angles to the last mentioned wall and substantially parallel with the plane of the prong containing wall, the outwardly extending portion having a perforation so spaced from the prongs as to be coaxial with the center face plate securing screw of a dual service outlet when the prongs are received in one side of said outlet, whereby a single securing screw may be inserted through both the clip and the face plate to secure the device in place when the prongs are inserted in the outlet.

9. In a plug-in device, a casing, terminals in said casing for attachment of a lead cord, contact prongs projecting from the bottom of said casing for insertion in a service outlet, electrical connections between said prongs and terminals, said casing having an opening in a wall at right angles to its bottom, a clip including a hook-like portion hooked over the edge of said opening and a portion lying closely along the wall having the opening, and a portion extending outwardly substantially at right angles to the last mentioned wall and substantially in the plane of the bottom of the casing, the outwardly extending portion having a perforation so spaced from the prongs as to be coaxial with the center face plate securing screw of a dual service outlet when the prongs are received in one side of said outlet, whereby a single securing screw may be inserted through both the clip and the face plate to secure the device in place when the prongs are inserted in the outlet.

HAROLD K. ANDREWS. 

